Unit IIntroduction tothe Science of GeneticsAgripa, Vanessa Abigail M.Seda, Sarah Jane P.
A brief HistoryOf Genetics
A brief History of Genetics• The genetics started with the work of the Augustinian friar Gregor Johann Mendel. His work on pea plants, published in 1866, described what came to be known as Mendelian Inheritance.• 1900 marked the "rediscovery of Mendel" by Hugo de Vries, Carl Correns and Erich von Tschermak, and by 1915 the basic principles of Mendelian genetics had been applied to a wide variety of organisms—most notably the fruit fly Drosophila melanogaster.
• Led by Thomas Hunt Morgan and his fellow "drosophilists", geneticists developed theMendelian, which was widely accepted by 1925. Alongside experimental work, mathematicians developed the statistical framework of population genetics, bringing genetic explanations into the study of evolution.• With the basic patterns of genetic inheritance established, many biologists turned to investigations of the physical nature of the gene. In the 1940s and early 1950s, experiments pointed to DNA as the portion of chromosomes (and perhaps other nucleoproteins) that held genes.
Genetics Today• Genetics Today objectives are oriented to the following aspects:• To provide the required genetic information associated with human disease• To integrate related disciplines such as biology, chemistry, molecular biology and epidemiology with modern genetics, in particular with genomics and epigenomics• To promote clinical application of innovative new genetic approaches• To offer an interdisciplinary forum for the discussion of new developments based on genetics knowledge• To apply genetics as an important tool for the development of new therapeutic alternatives for the treatment of human disease conditions• To improve the knowledge and practice of medical genetics Genetics Today will publish original articles, short communications, comments, letters to the Editor, and review articles upon invitation.
Branches of Genetics
Branches of Genetics• Cytogenetics The heredity units or genes are formed of DNA. These are integral part of chromosomes. The chromosomes are contained in the nucleus. The nuclei of germ cells are the only bridge between successive generations. The study of genes in the cell is called Cytogenetics.• Biochemical Genetics The chemistry of chromosomes, genes and nucleic acids and the chemistry of various processes related to them are studied with the help biochemistry. The branches of science which is considered with the biochemical study of genetic material are named as Biochemical Genetics.
Branches of Genetics• Physiological Genetics Genetics helps in explaining some very important physiological characteristics like blood groups, Rh factor, alkaptoneuria, sex differentiation and sex determination. Some physiological abnormalities like sickle cell anemia etc can be explained with the aid of genetic knowledge.
Branches of Genetics• Clinical Genetics Genetics has also helping in finding out the root cause of certain diseases like hemophilia, diabetes etc. All these diseases are caused on account of defective genotype. Moreover serology and blood transfusion are two most important fields, where genetics has directly assisted physiology and helped in saving life.• Radiation Genetics The study of effects of radiations on genes and the changes in their expression is being studied widely in the field of Radiation Genetics
Importance of Genetics• Genetic knowledge allowed vast improvement in productivity of domesticated plant species used for food (rice, wheat, corn). Genetic knowledge has also been a key component of the revolution in health and medical care in this century.• Bioengineering - directly altering the genetic material of an organism Developed by: Herbert W. Boyer and Stanley N. Cohen Allows segments of DNA to be moved to different locations or removed from the DNA molecule, thus acquiring new genes and new genetic traits• Health - About 3-5% of the world population (200 million people) are estimated to be afflicted by serious genetic disease Genetic knowledge has already allowed for treatment and genetic counseling (to prevent recurrence) of Down’s Syndrome and PKU Production of antibiotic resistant organisms Bioengineering offers the hope of creating more effective antibiotics Human Growth Hormone-treatment for dwarfism
Genetic Engineering• Alteration of an individuals genotype with the aim of choosing the phenotype of a newborn or changing the existing phenotype of a child or adult. It holds the promise of curing genetic diseases like cystic fibrosis, and increasing the immunity of people to viruses. It is speculated that genetic engineering could be used to change physical appearance, metabolism, and even improve mental faculties like memory and intelligence, although for now these uses seem to be of lower priority to researchers and are therefore limited to science fiction.
Application of Genetics• Biotechnology has commercial potential in medicine, agriculture, chemicals and the environment. Once concerned only with the production of genetically engineered proteins, the commercial biotechnology industry now includes the discovery and development of synthetic small-molecule chemical drugs (called biochemotechnology), gene therapy, cell therapy, carbohydrate engineering, DNA-coated silicon chips, and more.• The creation of transgenic animals and plants has generated huge markets for many countries. Genetically engineered fish and trees are revolutionizing the aquaculture and lumber industries. Transgenic crops currently on the market include soybeans, corn, cotton and canola. In 1999, almost half the area planted to transgenic varieties was almost half of the United States soybean crop and about 25 per cent of the United States corn crop. Most of the transgenic crop varieties are either herbicide
• Another area of the foods market where genetics has tremendous potential is nutraceuticals--foods whose nutritional value is enhanced. The current nutraceutical market of $17 billion is expected to grow in five years to be worth $250 billion annually. While nutraceutical are popular with consumers, so-called genetically modified foods are as yet controversial and the health risks associated with their consumption, while innocuous based on available evidence, remains a concern.
• While genetically engineered foods have yet to be widely embraced, biotechnology in the medical industry has exploded. Genetics has made it possible to understand how hereditary diseases and other familial traits are transmitted between generations. This has provided the opportunity to advise parents as to the likelihood of future offspring developing or transmitting certain conditions. Examination of embryonic fluid has made it possible to forecast whether an embryo will suffer from certain hereditary conditions at birth. Other medical applications dominate the biotechnology industry. In 1997, protein drugs of regular and genetically engineered natures had worldwide sales totaling nearly $24 billion, involving a bulk production of nearly one billion grams. The recombinant share comprised only 0.5 per cent of this bulk production. However, its share of dollars sales, about $12 billion, comprised about 50 per cent. Elsewhere, the industry is already developing genome-based drugs or gene therapy strategies against cancer, Alzheimers disease, Parkinsons disease, heart disease, diabetes, multiple sclerosis and AIDS.
References• http://www.bookrags.com/research/industrial-applications-of-genetics-wog/• http://www.nlm.nih.gov/medlineplus/• http://topnews.net.nz/content/212835-stem-cell-therapy-might-be-useful-treating-many-serious-diseases• http://www.citrusextracts.com/nutra.htm• http://www.biology-online.org/biology-forum/about827.html• http://www.butbn.cas.cz/ccala/index.php?page=sr&bol4=b4o&bol5=b5lo&locality=Russia• http://www.pachs.net/dialogues-with-darwin/item/100• http://www.biocourseware.com/iphone/ghistory/• http://www.dartmouth.edu/~bio70/• http://psych.colorado.edu/~carey/hgss2/pdfiles/Ch%2001%20History%20of%20Genetics.pdf• http://naturalselection.0catch.com/Files/gregormendel.html• ^ July 20 is his birthday; often mentioned is July 22, the date of his baptism. Biography of Mendel at the Mendel Museum• ^ "Gregor Mendel". Encyclopædia Britannica. Retrieved 21 July 2011.• ^ a b c Bowler, Peter J. (2003). Evolution: the history of an idea. Berkeley: University of California Press. ISBN 0-520-23693-9.• ^ Gregor Mendel, Alain F. Corcos, Floyd V. Monaghan, Maria C. Weber "Gregor Mendels Experiments on Plant Hybrids: A Guided Study", Rutgers University Press, 1993.• ^ a b c "The Mathematics of Inheritance". Online museum exhibition. The Masaryk University Mendel Museum. Retrieved Jan. 20, 2010.• ^ a b c "Online Museum Exhibition". The Masaryk University Mendel Museum. Retrieved Jan. 20, 2010.• ^ "The Enigma of Generation and the Rise of the Cell". The Masaryk University Mendel Museum. Retrieved Jan. 20, 2010.• ^ "Mendels Garden|[". The Masaryk University Mendel Museum. Retrieved Jan 20, 2010.• ^ Randy Moore (May 2001 vol=27). "The "Rediscovery" of Mendels Work". Bioscene.